Swimmer&#39;s fin



March 26, 1963 Fig.1

J. Y. COUSTEAU ETAL SWIMMER'S FIN Filed Sept. 1, 1959 its tts Ourinvention has for its object a swimniers fin or web to be fitted on aswimmers foot.

Swimmers fins as usually executed include a foot-gear section extendinginto a generally flat, ribbed, flaring and yielding element. When theswimmers feet beat, the yielding section is deformed, which increasesthe thrust exerted on the water.

With a view to obtaining during operation as automatic positioning intoits optimum position of the flat operative or propelling section of thefin and thereby to reducing to a minimum the eifort to be given by theswimmer, it has already been proposed. to separate the flat section fromthefoot-gear section of the fin by providing a transverse pivotal axisfor connecting said sections together; such fins are however moreintricate in their structure and consequently more expensive since theymust include two different sections provided with passageways for thepivotal axis and with stops.

Our present invention has for its object means for automatically settinginto its optimum position the fiat propolling section of .the. fin inthe manner disclosed hereinabove while resorting. to a simple unitaryfin structure devoid of any pivotal axis.

To this end and according to the invention, the propelling section ofthe fin is connected with the footgear section through the agency of anintermediate section the rigidity of which is less than that of theremainder of the fin.

The invention thus defined may be executed in practice in variousmanners which difier chiefly through the nature of the intermediate areaor section interconnecting the two sections of the fin as also throughthe fact that the flat section is rigid or deformable Within apredetermined extent.

Accordingly, it is possible to provide the fin according to theinvention with one or more of the following advantageous features:

The fin being made in the conventional manner of a single member ofdeformable material such as rubber for instance, the flat section isprovided with longitudinal ribs extending over a part of the footgearsection, but the rigidity of said ribs is weakened at points which aredistributed in a transverse plane containing the geometrical axiscorresponding to the desired hinge or pivotal connection.

The rigidity of the ribs is reduced by means of cuts provided acrosssame.

The cuts are formed only on one of the sides of the flat section.

The cuts are shaped in a manner such that their sides act as stopslimiting the maximum value of the angular shifting of the flat sectionof the fin round the pivotal axis with reference to the footgearsection, the curvature of the flat section not being taken into account.

The fin is provided with a medial area connecting the footgear sectionwith the flat section, which area is made of a material which is moreyielding than that forming said sections, so as to constitute a sort ofhinge between said two sections.

The flat section is perforated in its terminal area corresponding to thehinge.

The hinge area is reinforced in the part merging into the 3,'82,44ZPatented Mar. 26, 1963 flat section by a very yielding material showingaconsiderarble resistance against tractional and fiexional efforts suchas a fabric.

The accompanying diagrammatic drawings illustrate various embodiments ofthe invention and in particular:

FIGS. 1 and 2 are side views of a fin, the ribs of which are cut alongthe lower surface of the fin, FIGS. 1 and 2 corresponding to twodifferent angular positions of the propelling section.

FIG. 3 shows in side view and in three differentpositions a fin, theribs of which are provided with cuts both on the upper and lowersurfaces of the fin.

FIG. 4 is a plan view of the fin illustrated in FIG. 3.

FIG. 5 is a side view of a fin, the ribs of which are provided with cutsonly on the upper surface of the fin.

FIG. 6 is a side View of a fin wherein the intermediate area is made ofa material of a reduced rigidity.

In all said figures, the footgear section of the fin and the flatsection forming the actual fin are designated respectively by thereference numbers 1 and 2.

Generally speaking, the sections are provided on one or both surfaceswith ribs 3 as clearly shown in FIG. 4.

In accordance with the invention, the ribs are cut at 4 at least on oneof the sides of the flat section.

These cuts are V-shaped and arranged transversely as shown at XX (FIG.4) in a plane containing the geometrical pivotal axis between the twosections.

It is apparent from inspection of FIGS. 1, 2, 3 and 5' that the sides ofthe cuts 4 act as stops for limiting the angular shifting of the flatsection 2 in one direction only in the case of FIGS. 2 and 5 and in bothdirections in the case of FIG. 3 to a total value of about for instance.

The flexibility of the section 2 near the intermediate area may beincreased in the area XX by perforating it as shown at 5 in FIG. 4. Saidintermediate area may also be reinforced by a piece of fabric 6 as shownin FIGS. 3 and 4. In the particular fin shown in FIG. 6, the twosections 1 and 2 are connected by an intermediate Zone made with a kindof rubber more yielding than that of the remainder of the fin.

What we claim is:

1. A swimmers fin including a footgear section adapted to be fitted overthe swimmers foot, a flat, flexible, flaring and ribbed propellingsection extending forwardly from the toe portion of said footgearsection in prolongation thereof and an intermediate section integrallyconnecting said propelling section with said footgear section, therigidity of said intermediate section being lower than that of saidfootgear and propelling sections.

2. A unitary swimmers fin made of a yielding material and comprising afootgear section adapted to be fitted over a swimmers foot, a flat,flexible, flaring propelling section integral with the footgear sectionand cooperating with the toe end of said footgear section as anextension thereof and longitudinal ribs extending over at least themajor part of the surface of at least one side of said flat flexiblesection and over the adjacent part of the footgear section, means forreducing the rigidity of said ribs on their portion in transverseregistry with the cooperating ends of the two sections to produce apivotal connection between the two sections.

3. A unitary swimmers fin made of a yielding material and comprising afootgear section adapted to be fitted over a swimmers foot, a flat,yielding, flaring propelling section integral with the footgear sectionand cooperating with the toe end of said footgear section as anextension thereof and longitudinal ribs extending over at least themajor part of the surface of at least one side of said flat yieldingsection and over the adjacent part of the footgear section, the rigidityof which ribs is reduced through transverse cuts in transverse registrywith the cooperating 3 ends of the two sections to produce a pivotalconnection between the two sections.

4. A unitary swimmers fin made of a yielding material and comprisingafootgear section adapted .to be fitted yer a swimmers foot, a flat,yielding, flaring propelling section integral with the footgear sectionand operating with the toe end of said footgear section as an extensionthereof and longitudinal ribs extending over at least the major part ofthe surface of at least one side of said fiat yielding section and overthe adjacent part of the footgear section, said ribs being provided withtransverse cuts on one side of the yielding fiat section in registrywith the cooperating ends of the two sections to produce a pivotalconnection between the two sections.

5. A unitary swimmers fin made of a yielding material and comprising afootgear section adapted to be fitted over a swimmers foot, a flat,yielding, flaring propelling section integral with the footgear sectionand cooperating with the toe end of said footgear section as anextension thereof and longitudinal ribs extending over at least themajor part of the surfaces of both sides of said flat yielding sectionand over the adjacent part of the footgear section, said ribs beingprovided with transverse cuts on both sides of the yielding flat sectionin registry with the cooperating ends of the two sections to produce apivotal connection between the two sections.

6. A unitary swimmers fin made of a yielding material and comprising afootgear section adapted to be fitted over a swimmers foot, a fiat,yielding, flaring propelling section integral with the footgear sectionand cooperating with the toe end of said footgear section as anextension thereof and longitudinal ribs extending over at least themajor part of the surface of at least one side of said flat yieldingsection and over the adjacent part of the footgear section, the rigidityof which ribs is reduced through transverse cuts in V shape, intransverse registry with the cooperating ends of the two sections toproduce a pivotal connection between the two sections, the oppositesides of the cuts in each rib forming a stop defining the maximumflexing of the two sections with reference to each other.

7. A swimmers fin including a footgear section adapted to be fitted overthe swimmers foot, a flat, flexible, flaring and ribbed propellingsection extending forwardly from the toe portion of said footgearsection in prolongation thereof and an intermediate section integrallyconnecting said propelling section with said footgear section andperforations disposed in said intermediate section to provide a rigiditythereof which is lower than that of said footgear and propellingsections thereby increasing the flexibility thereof.

8. A swimmers fin including a footgear section adapted to be fitted overthe swimmers foot, a Hat, flexible, flaring and ribbed propellingsection extending forwardly from the toe portion of said footgearsection in prolongation thereof and an intermediate section integrallyconnecting said propelling section with said footgear section, therigidity of said intermediate section being lower than that of saidfootgear and propelling sections and a sheet of fabric insertedlongitudinally inside said intermediate section to impart reinforcementthereto.

References Cited in the file of this patent UNITED STATES PATENTS1,983,609 Hudson Dec. 11, 1934 2,099,973 De Corlieu Nov. 23, 19372,343,468 Messinger Mar. 7, 1944 2,595,643 Daugherty May 6, 19522,623,574 Damsch Dec. 30, 1952 2,669,036 Israel Feb. 16, 1954 2,711,033Dick June 21, 1955 2,715,231 Marston Aug. 15, 1955 2,738,598 Inga Mar.20, 1956 2,765,545 Conrad Oct. 9, 1956 2,779,077 Kline Jan. 29, 19572,903,719 Wozencraft Sept. 15, 1959 FOREIGN PATENTS 502,065 Italy Nov.26, 1954

1. A SWIMMER''S FIN INCLUDING A FOOTGEAR SECTION ADAPTED TO BE FITTEDOVER THE SWIMMER''S FOOT, A FLAT, FLEXIBLE, FLARING AND RIBBEDPROPELLING SECTION EXTENDING FORWARDLY FROM THE TOE PORTION OF SAIDFOOTGEAR SECTION IN PROLONGATION THEREOF AND AN INTERMEDIATE SECTIONINTEGRALLY CONNECTING SAID PROPELLING SECTION WITH SAID FOOTGEARSECTION, THE RIGIDITY OF SAID INTERMEDIATE SECTION BEING LOWER THAN THATOF SAID FOOTGEAR AND PROPELLING SECTIONS.